New Threat: An image grab taken from a propaganda video uploaded on June 11 by the Islamic State allegedly shows militants driving in Iraq. (AFP/Getty Images)

DUBAI — Militants with the Islamic State (IS) are increasingly relying on terror tactics and suicide squads, and the method was key in their recent capture of one of Syria’s largest air bases, experts say.

IS fighters captured the strategic Tabqa air base in the Raqqa province after raging battles since Aug. 19, tallying more than 170 members of government forces and over 360 IS fighters, according to the Syrian Observatory for Human Rights.

The weeks of fighting for control of Tabqa air base has featured a terror strategy by a group of special IS fighters named “Inghimasy,” or infiltrators, who operate with a “ready-to-die” attitude, said Hassan Hassan, Syrian affairs expert and research associate at United Arab Emirates-based Delma Institute.

“The regime put a very good fight but [IS] has taken all the facilities in Raqqa surrounding the base,” Hassan said. “As the base became isolated, IS designated about 100 Inghimasy suicide bombers who weakened the defenses.”

Hassan said the Inghimasy suicide team gets into close-quarter positions on the front lines. “If they succeed they move from one area to another. If they fail to break through, they blow themselves up and their opposition, creating holes in the enemy lines.”

Syrian government forces could not afford to send support to the base because of the continuous flow of the Inghimasy fighters, as that would drain their already stretched resources.

Hassan added that a fierce reputation has grown about these fighters. “When they enter a battlefield, government forces withdraw after they [IS] gain between 50 to 60 percent of the ground from fear of being captured and beheaded or crucified,” he said.

The recent spate of social media videos and images released by IS fighters has spread across the planet in massive scale, including to Syrian forces themselves.

Furthermore, the progression of the militants through the Sunni heartlands of Iraq this year has been accompanied by shocking levels of brutality, said Nigel Inkster, the former operations director for MI6 and the current director of Transnational Threats and Political Risk at the International Institute for Strategic Studies.

“The group — which began as al-Qaida in Iraq before rebranding itself as ISIS [Islamic State of Iraq and al-Sham] — has made a show of beheading or crucifying hundreds of opponents,” he wrote in an article posted on the institute’s website.

“This cruelty is part of a calculated strategy designed to instill fear in potential opponents and purvey an image of invincibility. But until this week it had attracted relatively little attention from Western media,” he added.

A call for professionals to move to Iraq and Syria issued by the self proclaimed Emir Abu Bakr al-Baghdadi of the Islamic Caliphate in July has also expanded the problems.

The leader of the militant group called on Muslims with military, medical and managerial skills to join the pan-Islamic state stating: “Those who can immigrate to the Islamic State should immigrate, as immigration to the house of Islam is a duty.”

The flow of Western-educated militants joining the ranks of experienced fighters can further expand IS’ capabilities, Hassan said.

“IS fighters for years have gained solid experience fighting American forces,” he said. “They seized stockpiles of weapons and are well taught and trained.”

Inkster wrote that the issue of radicalization among the West’s Islamic-minority populations has been long-running and is particularly susceptible to alarmist portrayal in the global media. However, the problem is real and not easily solvable.

“Many young Muslims, for one reason or another, find life in the West boring and unrewarding and are easily attracted by the glamour and excitement of life as combatants motivated by a cause, however wrong-headed that cause may seem to others,” he wrote.

“Overall, the numbers are still small and much work is being done by governments to engage Islamic communities to reduce the risks of further contagion. But more thought needs to be given to convincing young jihadists who become disillusioned with jihad that there is a way out for them that does not automatically lead to prolonged incarceration.” ■